I honestly could not believe my eyes when I came across this article. Growing bigger, better diamonds???? Science is really fascinating! It truly amazes me at times how science can create wonders when I read interesting articles like these.

Take a look!

Scientists grow bigger, better diamonds

Using chemical vapor deposition, gems can be grown very rapidly

If you thought that rock on the ring in the window of Tiffany’s was big and beautiful, the diamonds treated in labs with a newly-developed method will really blow you away.

Diamonds grown in the laboratory using a chemical vapor deposition process can be treated by a new high temperature, low pressure method to improve their color and optical clarity.

Diamond, a particular form of pure carbon, is of course used for more than adding sparkle to jewelry. It is also used for making scalpel blades, electronic components, and even quantum computers.

But the very properties of diamond that make it perfect for these uses — its hardness (it’s the hardest known naturally-occurring mineral), optical clarity and resistance to chemicals, radiation and electrical fields — can also make it a difficult substance to work with.

Defects can be purged from diamond by a heating process called annealing, but this process can turn diamond into graphite, another form, or allotrope, of carbon that is soft and gray and used in pencil leads.

To prevent graphitization, diamond treatments have previously required using high pressures (up to 60,000 times atmospheric pressure, or the pressure we experience at sea level) during the annealing process, but such high pressure/high temperature processes are expensive and put limits on the size and amounts of diamonds that can be treated.

A team of scientists at the Carnegie Institution in Washington, D.C., have found away to get around these issues — and make bigger, better diamonds.

Growing diamonds
They use a method called chemical vapor deposition (CVD) to grow synthetic diamonds. Unlike other diamond-growing methods that use high pressures like those found deep in the Earth where natural diamonds are formed, CVD produces single-crystal diamonds at low pressure. These diamonds can be grown very rapidly and have relatively few defects.

The Carnegie team could take these synthetic diamonds and anneal them at temperatures up to 3,632 degrees Fahrenheit (2,000 degrees Celsius) at pressures below atmospheric pressure. The annealing process turns the diamond crystals, which are originally yellow-brown, colorless or light pink. The process also has minimal graphitization.

“It is striking to see brown CVD diamonds transformed by this cost-efficient method into clear, pink-tinted crystals,” said study team member Chih-shiue Yan.

The researchers also figured out what causes the pink tint: A nitrogen atom takes the place of a carbon atom in certain place in the crystal structure. This finding “may also help the gem industry to distinguish natural from synthetic diamond,” Yan said.

The new method, detailed in the Oct. 27 issue of the journal Proceedings of the National Academy of Sciences, also lets the researchers grow diamonds bigger.

“The most exciting aspect of this new annealing process is the unlimited size of the crystals that can be treated,” said study team member Ho-kwang Mao. “The breakthrough will allow us to push to kilocarat diamonds of high optical quality.”

October 9, 2008

I guess I’m taking a roller coaster ride with regards to the issue. Depends on what I come across.

Back to education for you folks! Found some cool stuff on the geology aspect of diamonds.

I had a taste of this topic while I was taking the subject. Cool stuff

Enjoy!

The Properties of Diamonds

Diamonds are found as rough stones and must be processed to create a sparkling gem that is ready for purchase.

As mentioned before, diamonds are the crystallized form of carbon created under extreme heat and pressure. It’s this same process that makes diamonds the hardest mineral we know of. A diamond ranks a 10 on the Mohs Hardness Scale. The Mohs Scale is used to determine the hardness of solids, especially minerals. It is named after the German mineralogist Friedrich Mohs. Here’s the scale, from softest to hardest:

1.Talc – easily scratched by the fingernail

2.Gypsum - just scratched by the fingernail

3.Calcite – scratches and is scratched by a copper coin

4.Fluorite - not scratched by a copper coin and does not scratch glass

Even though diamond is only one level higher on the scale than corundum, diamond can be anywhere from 10 to hundreds of times harder than this class of gems.

Rough Diamonds

It is the molecular structure of diamonds that makes them so hard. Diamonds are made of carbon atoms linked together in a lattice structure. Each carbon atom shares electrons with four other carbon atoms, forming a tetrahedral unit. This tetrahedral bonding of five carbon atoms forms an incredibly strong molecule. Graphite, another form of carbon, isn’t as strong as diamond because the carbon atoms in graphite link together in rings, where each atom is only linked to one other atom.

September 17, 2008

Hahaha I am guess you must be getting a tad tired of reading about famous diamonds no?

I can assure you that it won’t go on forever. Just a couple more *grins*

Hey, I have to give ALL these world famous diamonds their ‘one-minute’ fame!

With that, I introduce you to the diamond version of a golden egg….the “Golden Jubilee”

Golden Jubilee

Discovered in the Premier mine in South Africa in 1986, the 755.50 carat rough diamond was a beautiful golden yellow colour with a bright reddish hue at the centre. (didn’t I say it is the diamond version of the ‘golden egg’?)

Gabi Tolkowsky commented that “within its heart lay a wonderfully mysterious shine that gave the diamond a character unlike any other”.

A large surface and deep cracks from the interior, as well as several inclusions, meant that cutting and polishing the big diamond presented challenges.

An underground room that was free from vibration had to be constructed before work could begin on the diamond. In 1990, after two years of work, the stone was finished, reduced in total from 755.50 carats, to 545.65 carats.

Gabi Tolkowsky described the cut as a “Fire-Rose cushion shape.”

Thai businessmen arranged for the diamond to be given to King Bhumibol as a gift from the people to celebrate the 50th anniversary of the King’s ascent to the throne.

The diamond was named the Golden Jubilee, and was received by the King’s daughter, Princess Matia Chari Sirindhom, on his behalf in 2000.

The diamond is now on display in the Royal Museum at Pimammek Golden Temple Throne Hall in Bangkok.

September 16, 2008

Continuing from where I left off, here is another “sparkling” story which places South Africa as “diamond haven”

Enjoy! :)

The Eureka Diamond is perhaps the single most important diamond in the history of South African mining.

Discovered in 1866 by children digging amongst the shrubbery of their father’s land, it remained for some time “undiscovered” – a mere plaything for the children of Dutch farmer Daniel Johannes Jacobus Jacobs.

No one in the farmer’s home took it to be anything more than an attractive rock, and it was not until a neighbour farmer, Schalk van Niekerk, who possessed a smattering of geological knowledge noticed the stone whilst visiting the Jacobs’ farmhouse.

Whilst van Niekerk did not imagine it could be a diamond he thought it interesting enough to offer to buy the Eureka from the children. However, Mrs Jacobs refused to accept any payment and simply gave the stone to her neighbour. (how I wish I was the neighbor! hahaha)

The Eureka then passed to John Robert O’Reilly who van Niekerk took the stone to in order to confirm his suspicions that it might be a rare mineral. O’Reilly determined that it had to be a diamond and it was sent to Dr. William Guybon Atherstone in Grahamstown for authentication.

In 1867 Atherstone confirmed the “first” diamond to be discovered in South Africa, stating it was a “veritable diamond weighing 24 carats worth £800″, he suggested that the Eureka be exhibited at the Cape Colony’s stand at the Paris exhibition.

However it was felt that Queen Victoria should be given the opportunity of inspecting the diamond firsthand so a replica was exhibited and the Eureka was sent on its long journey to Windsor.

The stone was then sold to Sir Philip Wodehouse, Governor of the Cape Colony for £500; O’Reilly and van Niekerk sharing the proceeds. Whilst an agreement had been made that van Niekerk would give some of his share to the Jacobs family, it seems they never received a penny for their great discovery.

In 1870 Sir Philip returned to the UK, and there the Eureka was to remain for almost 100 years. It was cut and, over the course of almost a century, changed hands a number of times.

In 1946 the Times reported that £5,700 had been paid at a Christie’s public auction for a diamond bangle of 20 large stones with the Eureka as its centrepiece.

It remained in a private collection until, in 1967, exactly 100 years after its discovery, De Beers purchased the Eureka, gifting it to the people of South Africa.

The Eureka was placed on permanent loan by the South African government at the Mine Museum, Kimberley – a fitting venue to display the gemstone that established South Africa as one of the world’s richest resources of diamonds.

Don’t you wish you found a diamond in your backyard now?…..I DO! *grins*

September 11, 2008

Picking up from the first post of famous diamonds, here is the next in line….Agra

If I were to describe this gem in one word, it would be “captivating”.

Introducing the Agra!

Agra

Agra is the site of the Taj Mahal, one of the most beautiful buildings in the world. The diamond has a long history, with many of the earlier accounts disputed.

It has been suggested that in 1526 the Agra diamond was taken into the possession of Babur, the first Mogul Emperor, after he defeated the Rajah of Gwalior in battle. It is recorded that Babur wore the Agra diamond in his turban.

In 1739, the Agra may have been amongst loot captured by Nadir Shah when the Persian sacked Delhi, however the gem eventually returned to India.

The diamond was reputedly smuggled to England by young military officers in around 1857, in the year of the Indian Mutiny. However the Agra was apparently already in the possession of the Duke of Brunswick, who had paid the huge price of 348,600 francs for the stone.

Later in the 19th century, the Agra was reduced to just under 32 carats, to eliminate some black inclusions. Even at this stage it was questioned whether the Agra was indeed the same stone that some thought it was.

More formal records indicate that Edwin Streeter purchased the Agra from Bram Hertz, with Hertz giving Streeter over £15,000 in jewels and cash in return.

Despite a lengthy lawsuit relating to the Agra, the stone remained in Streeter’s stock until 1904 when the Parisian jewellers La Cloche Freres, put the item up for sale at Christie’s in 1905.

Shortly after 1909 the gemstone was acquired by Louis Winans, son of a wealthy American railroad engineer. Louis Winans settled in Brighton and used a local jeweller to help him create a stunning collection of coloured diamonds.

In 1990, the Agra and two other diamonds from the collection were auctioned at Christie’s. The vendor had inherited them in 1927, and during the Second World War had buried them in the garden for safe keeping.

The Agra was certified as a fancy light pink natural coloured VSI2, and sold for £4,070,000, making it at that time, the most expensive pink diamond in the world.

Since then, the Agra has again been recut, to 28.15 carats.

What a history! Wouldn’t it be interesting if one could travel through time and watch how all these events took place? :)

September 10, 2008

There are a few famous diamonds I would like to talk about but I shall not overwhelm you with its ‘sparkling’ history. Thus I shall dedicate each post to these magnificent gems. De Beers, the frontrunner in the diamond producing industry celebrated their Centenary with style. What better way than to show the world what they dug out of their backyard (pun intended, lol)

For thousands of years diamonds have been valued for their beauty and rarity, entrancing us with their fire and brilliance. Symbols of financial wealth, power and inspiration, diamonds are also a token of love and personal expression of our hopes for the future and an emblem of eternity.

So what makes a diamond famous? Rarity is often the most important factor. This may mean size, but extraordinary variety or intensity of colour can also make a diamond famous. Large flawless diamonds – those with the best colour and clarity grades – are among the rarest materials on earth.

Other factors are more closely linked to the history of the individual stone. Diamonds are often named after their owner, their country or mine of origin, their colour, their shape, a special occasion or the sentiments they evoke with their unique beauty.

The Centenary

The Centenary celebrations of De Beers took place in 1988 in Kimberley, in front of a captive audience of four hundred people. These included government representatives of producer countries and other important dignitaries from the diamond industry. Julian Ogilvie Thompson, the then Chairman, revealed that a diamond of 599 carats had been recovered from the Premier mine.

Over time, the Premier mine had produced approximately 300 stones of more than 100 carats, and nearly 25% of all the world’s diamonds over 400 carats. These included important stones such as the Cullinan, the Niarchos, the Taylor-Burton, and the Premier Rose.

When found in 1986, only a few people knew about its discovery, and were sworn to secrecy. The rough stone presented many difficulties in polishing it. One of the most accomplished cutters in the world, Gabi Tolkowsky, was chosen to study and appraise the great stone.

We have recovered at the Premier mine a diamond of 599 carats which is perfect in colour – indeed, it is one of the largest top colour diamonds ever found. Naturally it will be called the Centenary diamond.

Julian Ogilvie Thomson

He said of its top colour – “Usually you have to look into a diamond to appreciate its colour, but this just expressed itself from the surface. That is very rare.”

Generally, however, the rough shape of the diamond meant it would be difficult to cut, and with a number of alternative routes, including cutting the diamond into several smaller stones.

In the end Tolkowsky said the diamond was to be made into one large modern-cut stone.

Tolkowsky and two other cutters, Geoff Woollett and Jim Nash, worked with hand-picked engineers in a specially constructed room in the De Beers Diamond Research Laboratory in Johannesburg. The construction of the room itself took a year.

Meanwhile Tolkowsky studied the diamond. He said, “From the moment I knew I was going to cut it, I became another man, a strange man. I was looking at the stone in the day, and the stone was looking at me at night.

Kerfing by hand, Tolkowsky took 154 days to remove 50 carats, to reveal a rounded stone weighing approximately 520 carats. After many sketches, thirteen shapes were presented to the De Beers Board, and a modified heart shape was decided upon.

After nearly a year of work, the Centenary weighed 273.85 carats. It also had an unprecedented number of facets, with 164 on the stone and 83 on the girdle. Two flawless pear shapes were also cut.

The Centenary is the largest modern-cut diamond in the world, and is the ultimate expression of both “fire” and “brilliance”.

Nicky Oppenheimer remarked, “Who can put a price on such a stone?”

There you go, the first of the many famous diamonds…just look at the colors bouncing off the diamond! Magnificent! :)

Ever wondered how diamonds were formed? Well, I guess not many of us really give a thought about it when we shop for a gorgeous rock (yes it is essentially just a piece of rock, albeit a shiny one, haha!) in hope to see that priceless expression on the face of our loved ones.

Since I am in the educational mode, I figured it’ll be worthwhile to know how diamonds are formed! Here’s an article I found that would help expand your geological knowledge.

Enjoy!

Since the early 1980s, a vast amount of new scientific information has become available on the origin of diamonds.

Much of this information has been obtained through the study of ‘inclusions’- natural material found within diamonds.

Diamonds were formed at least 990 million years ago, although some are estimated to be as many as 4.25 billion years old, thereby pre-dating life on this planet.

Diamonds are formed at pressures of 45-60 kbar. A kilobar is a metric unit for measuring high pressure. This corresponds to a depth of 125-200 kilometres below the Earth’s surface where the pressure is around fifty thousand times that of atmospheric pressure at the Earth’s surface.

Some diamonds form at depths of 300-400 kilometres, or even deeper, but these diamonds are particularly rare.

Diamonds are formed at temperatures between 900°C and 1,300°C.

Formation of Kimberlite pipe

In the Earth’s upper mantle, the pressure of magma, or molten rock, cracks the surrounding rock around 125km below the Earth’s surface. The magma contains dissolved carbon dioxide, which begins to bubble and expand, either due to heat from below or reduced pressure from above.

This expansion causes the magma to erupt explosively up through the cracks, like an uncorked champagne bottle.

The resulting explosion is vastly more powerful than most volcanoes, with molten rock rising to the surface at the speed of sound, forming a ‘pipe’ through the path of least resistance to the surface.

The magma rises so quickly that diamonds do not have time to convert to graphite, which is the more stable form of carbon at the Earth’s surface. Once the diamonds cool down, they don’t have enough energy to re-form their crystal structure into graphite.

The volcanic cone eventually cools and the magma hardens into kimberlite. It then starts to be eroded and weathered away by the elements. Eventually, it becomes almost undetectable on the surface.

Now THIS was what got my attention!

Types of Diamond Deposits

Primary depositsDiamondiferous pipes, which are ‘pipes’ of mineral-rich volcanic rock containing diamonds, are known as primary deposits.

Diamondiferous pipes are the solidified cores of kimberlite or lamproite volcanoes.

Secondary depositsDeposits that contain diamonds which have travelled some distance from their original source are referred to as secondary deposits.

The diamonds that are now found in Namibia, for example, have travelled over 1,000 miles from their original source in southern Africa, transported by the Orange River.

Kimberlite, lamproite and komatiite are the only types of rock known to have transported diamonds from the Earth’s interior up to the surface in significant quantities.

September 3, 2008

Diamonds are forever. Diamonds are a fascination. They evoke feelings of wonder and awe in the eyes of some and romance in the hearts of others.

This article below serves as a crash course in understanding the different aspects that makes a diamond what it is. I hope you’ll be somewhat educated by the end of it :)

Cut

Cut refers to the angles and proportions of a diamond. It is the only one of the 4Cs that is influenced by the human hand.

Diamond cutting requires great skill and training. The cutter must polish tiny surfaces known as facets onto the rough diamond. This process is what creates the facets known as the crown, culet, table, girdle and pavilion of the diamond.

To cut a diamond perfectly, a craftsman will often need to cut away more than 50% of the rough diamond.

A well-cut diamond will internally reflect light from one mirror-like facet to another and disperse and reflect it through the top of the gem. The facets, when arranged in precise proportions, will maximize the fire life and brilliance of a diamond.

A well-cut diamond will be higher in quality and value than deep or shallow-cut diamonds. Diamonds that are cut too deep or too shallow lose or leak light through the side or bottom, resulting in less brilliance and a less valuable stone.

Cut also refers to the shape of a diamond – round, square, or pear, for example.

Round diamonds are symmetrical and capable of reflecting nearly all the light that enters, so it is the most brilliant of all diamond shapes and follows specific proportional guidelines.

Non-round shapes, also known as ‘fancy shapes’ have guidelines in order that they are considered to be well-cut.

Carat

Carat refers to the weight of a diamond.

Often mistaken with size, carat it is actually a measure of weight.

The term carat is a derivative of the word carob. Carob seeds, which are surprisingly uniform in weight, were used as a reference for diamond weight in ancient civilisations. One carob seed equalled one carat.

One carat is equivalent to 200 milligrams. One carat can also be divided into 100 ‘points’. A .75 carat diamond is the same as a 75-point or 3/4 carat diamond.

Since larger diamonds are found less frequently in nature, a single 1-carat diamond will cost more than two 1/2-carat diamonds, assuming the colour, clarity and cut are the same.

Cut and mounting can make a diamond appear larger or smaller than its actual weight. A diamond’s setting should always optimise its beauty.

Color

Colour refers to the degree to which a diamond is colourless.

Diamonds can be found in many colours, however white-coloured or colourless diamonds remain the most popular.

Diamonds are graded on a colour scale which ranges from D (colourless) to Z. Warmer coloured diamonds (K–Z) are particularly desirable when set in yellow gold. Icy winter white coloured diamonds (D–J) look stunning set in white gold or platinum.

Colour differences are very subtle and it is very difficult to see the difference between an E and an F, for example. Therefore, colours are graded under controlled lighting conditions and are compared to a master set for accuracy.

Truly colourless stones, graded D are treasured for their rarity. Colour, however, is subjective. The Incomparable, one of the world’s most beautiful diamonds, contains hints of brown, smokey amber and champagne colours.

Nature has also created diamonds in shades of blue, green, yellow, orange, and pink. Red is the rarest of all. These diamonds are called ‘coloured fancies’ and are extremely rare and highly treasured.

Clarity

Clarity refers to the presence of inclusions in a diamond.

Naturally-occurring features called inclusions provide a special fingerprint within the stone. Inclusions are natural identifying characteristics such as minerals or fractures, occurring while the diamond was being formed in the Earth.

The majority of these natural birthmarks are invisible to the naked eye, yet they affect the way light is reflected and refracted within the stone.

Inclusions appear as different shapes, such as crystals, clouds or feathers. These idiosyncrasies often add to the overall character of the diamond.

Containing several birthmarks or inclusions, the Excelsior is considered one on the world’s most beautiful diamonds.

Most inclusions are not visible to the naked eye unless magnified.

To view inclusions, gemologists need to use a magnifying loupe that allows them to see a diamond at 10x its actual size.

Inclusions are ranked on a scale of perfection, known as clarity. The clarity scale, ranging from F (Flawless) to Included (I), is based on the visibility of inclusions at a magnification of 10x.

Even with a loupe, the birthmarks in the VVS (Very, Very Slightly Included) to VS (Very Slightly Included) range can be very difficult to find. It is only when a diamond is graded ‘I’ that it is possible to see the birthmarks with the naked eye.

The position of inclusions can affect the value of a diamond and you should consider the number, size, brightness, nature and position of inclusions.

Some inclusions can be hidden by a mounting, and have little effect on the beauty or brilliance of a stone. An inclusion in the middle or top of a diamond could impact the dispersion of light, sometimes making the diamond less brilliant.

There are very few flawless diamonds found in nature, making these diamonds much more valuable.